Intrauterine devices (IUD): birth control

IUDs prevent unwanted pregnancies, but don’t protect against STIs. Use a condom.

Intrauterine Devices are 94% to 99% effective.

What is an IUD?

The Intrauterine Device (IUD) is a small, plastic, T-shaped object with strings attached to it. It is inserted into the uterus by a doctor. Some types of IUDs have a copper covering and others release a hormone.

How does an IUD work?

IUDs work primarily by preventing sperm from fertilizing an egg. The IUD that releases hormones also causes some changes to the lining of the uterus and cervical mucus that prevent fertilization.

How effective is an IUD?

IUDs are 94 to 99% effective at preventing an unplanned pregnancy.

What are the possible side effects of using an IUD?

Hormonal IUDs

• irregular periods for the first few months
• weight gain
• lower abdominal pain
• moodiness
• breast tenderness

Copper IUDs

• heavier periods with increased cramping

What are the advantages of using an IUD?

• you don’t have to do anything before or after sex
• you can leave it in for up to five years
• lighter and eventually no periods
• it doesn’t affect your ability to get pregnant in the future

What are the disadvantages of using an IUD?

• it must be inserted and removed by a doctor
• insertion can be uncomfortable

Where can I get an IUD?

An IUD can be prescribed and inserted by a gynaecologist. Some family physicians also insert IUDs.

*The IUD offers no protection against sexually transmitted infections (STIs), including HIV/AIDS.

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This item was last modified on June 12, 2015